Verified answer

multiply the numerators: 4y^4 5b^2 = 20 y ^4 b^2

multiply the denominators: b^4 y 6 y = 6 b^4 y^2

reduce like bases:

20 / 6 = 10/3

b^2 / b^4 = 1 / b^2

y^4 / y^2 = y^2 / 1

put it back together:

10y^2 / 3b^2

that's it! ;)

You can cross cancel like terms to make this problem easier.

4y^4/b^4y • 5b²/6y =

working with 4y^4 and 6y. Each is divisible by 2 and one y will cancel out leaving

2y³/b^4y • 5b²/3 =

now working with b^4y and 5b². Cancel out a b² from each term leaving.

2y³/b²y • 5/3 =

now working left side term you can cancel out one y leaving

2y²/b² • 5/3 = 10y²/3b²